本篇的重點內容是利用openlayers實現風場圖功能，效果圖如下：

實現思路

• 界面設計

//風場圖
"<div style=‘height:25px;background:#30A4D5;margin-top:10px;width: 98%;margin-left: 3px;float: left;‘>" +
             "<span style=‘margin-left:5px;font-size: 13px;color:white;‘>風場圖</span>" +
        "</div>" +
       ‘<div id="windLayer" style="padding:5px;float: left;">‘ +
            ‘<input type="checkbox" name="windlayer" style="width: 15px;height: 15px;vertical-align: middle;margin: auto;"/>‘ +
            ‘<label style="font-weight: normal;vertical-align: middle;margin: auto;">風場圖</label>‘ +
‘</div>‘ 

• 點擊事件

//風場圖
$("#windLayer input").bind("click", function () {
            if (this.checked) {
                var layer = bmap.getMapConfig().getShareLayer("GISSERVER_Wind");
                bxmap.olWindLayer.Init(bmap);
                if(layer){
                    layer.setVisible(true
 
);
                }
                //圖例面板顯示
                $("#map_tl").css("display","block");
                $("#map_tl>img").attr(‘src‘, getRootPath() +"js/main/olWindLayer/windLegend.jpg");
                $("#map_tl>img").css("width","auto");
                $("#map_tl>img").css("height","300px");
            }
            
 
else {
                var layer = bmap.getMapConfig().getShareLayer("GISSERVER_Wind");
                bxmap.olWindLayer.clearWind();
                if(layer){
                    layer.setVisible(false);
                }
                //圖例面板隱藏
                $("#map_tl").hide();
            }
})

• 初始化代碼

var bxmap = bxmap || {};
bxmap.olWindLayer = {
    map:null,
    wind:null,
    Init:function(bmap){
        this.map = bmap.getMap();
        this.map.getView().setCenter([13501836.676, 2751733.018]);
        this.map.getView().setZoom(3);
        //加載風場數據
        var wind, data;
        axios.get(getRootPath() +"js/main/olWindLayer/gfs.json").then(function (res) {
            if (res.data) {
                data = res.data
                wind  = bxmap.olWindLayer.wind = new WindLayer(data, {
                    projection: ‘EPSG:3857‘,
                    ratio: 1
                })
                wind.appendTo(bxmap.olWindLayer.map)
            }
        });
    },
    clearWind:function(){
        if(bxmap.olWindLayer.wind)
           bxmap.olWindLayer.wind.clearWind();
    }

}

openlayers入門開發系列之風場圖篇